Articulated roller assembly

ABSTRACT

An earth compacting machine utilizing in-line vibratory roller drums, each associated with a respective frame section and the frame sections being joined together by an articulated coupling. Vibratory means is disposed in individual drums. Hydraulic means under the control of a riding or walking operator powers the vibratory means, effects either forward or reverse traversal of the machine by positively rotating the roller drums, and enables steering by a powered angular movement of one of the roller drums. A novel steering system of general application amplifies steering input signals and incorporates a simplified follow-up mechanism to assure accurate, sensitive response to such signals.

United States Patent 1191 Carnahan et a1.

[ June 4, 1974 1 ARTICULATED ROLLER ASSEMBLY [75] Inventors: John T. Carnahan; Eugene C.

Briggs, both of Dayton, Ohio 22] Filed: Dec. 13, 1971 {21] A l. No.: 207,185

[52] US. Cl. 404/117, ISO/79.2 B [51] Int. Cl. E0lc 19/28 [58] Field of Search 94/50, 50 V; 180/792,

[56] References Cited UNITED STATES PATENTS 1,999,834 4/1935 Ernst 137/101 X 2,374,410 4/1945 Brumbaugh ISO/79.2 B 3,303,762 2/1967 Jennings 94/50 V 3,394,641 7/1968 Steck 4 94/50 R 3,543,656 12/1971) Roettger 1 94/50 v 3,568,868 3/1971 Chichester 137/101 X 3,623,407 11/1971 Dresher 94/50 V FOREIGN PATENTS OR APPLICATlONS 1,201,130 8/1970 Great Britain 94/50 Primary Examiner-Roy D. Frazier Ass/stun! E.\'aminer-Thomas J. Holko Attorney, Agent, or Firm-Jerome P. Bloom [57] ABSTRACT An earth compacting machine utilizing in-line vibratory ro11er drums, each associated with a respective frame section and the frame sections being joined together by an articulated coupling. Vibratory means is disposed in individual drums. Hydraulic means under the control of a riding or walking operator powers the vibratory means, effects either forward or reverse traversal of the machine by positively rotating the roller drums, and enables steering by a powered angu1ar movement of one of the roller drums. A novel steering system of general application amplifies steering input signals and incorporates a simplified follow-up mechanism to assure accurate, sensitive response to such signals.

24 Claims. 11 Drawing Figures :ATENTEDJUN 4 I974 SHEET 2 BF 6 PATENTEDJUN 41974 SHEET 6 0F 6 FlG-i ARTICULATED ROLLER ASSEMBLY BACKGROUND OF THE INVENTION This invention relates to contractors equipment. and particularly to self-propelled vibratory rollers useful in earth compacting, asphalt finishing and the like. Although not so limited the invention has special reference to machines providing a pair of roller drums in tandem arrangement, separate machine sections being interconnected by an articulated coupling obviating the creation of undue stress and enabling steering by an angular turning motion of one of the roller drums.

To such extent as self-propelled vibratory rollers exist in the prior art they do not lend themselves to ease of operation, do not effectively vibrate the roller drum or drums due to relatively remote application of the vibratory impulses, and are difficult to steer. They tend moreover to be massive in size, limiting their usefulness in close work and in small area jobs. Nor are they readily adaptable either to earth compacting or to asphalt finishing. Insofar as is known, vibratory rollers of the prior art do not comprise a machine having dual roller drums and characterized by articulated power steering, powered forward and reverse drive and vibratory means in the roller drums.

SUMMARY OF THE INVENTION The present invention provides a small articulated vibratory roller. Dual in-Iine roller drums are selfcontaining with respect to vibratory apparatus and are mounted to be rotated relatively to a supporting frame, as well as relatively to be vibrated. The machine includes a prime mover and power connections extending to each roller drum for individual drive and vibration thereof. In a traverse movement, the machine compresses the work by the application thereto of the roller drums and introduces a supplemental compaction force by a simultaneous vibration of the drums. According to a feature of the invention the vibratory action may be discontinued and in conjunction therewith the powered rotary drive to the roller drums augmented. Relatively rapid travel of the machine without vibration is possible under this condition, as in moving the machine from one working site to another. According to a further feature of the invention, hydraulic power is utilized in the traverse drive of the machine, in the vibration of the roller drums and in steering. Controls are made conveniently accessible to a riding or walking operator, the ease of handling of the machine made possible by such controls and by the hydraulic power regulated thereby offering a major design advantage over other known compactors. The provided power steering is of exceptional simplicity and has general application, though particularly advantageous in application such as here described. In its broader aspects is generally applicable to hydraulic and other servo-systems achieving powered amplification of steering and like signals. In the preferred embodiment illustrated it utilizes a Bowden wire type cable wherein the cable describes a loop having a changing radius responsive to changes in the angular position of the steered roller drum, such changes having a followup or cancellation effect upon introduced input signals.

Vibration of the roller drums is carried out by hydraulic means individual to each drum enabling variation in the frequency of vibration as between forward and rearward roller drums. A built-in amplification factor, relative to the natural frequency of the soil being compacted may be selected for most advantageous soil compaction.

In its various aspects which together produce an improved compactor roller, the invention also specifically provides a unique vibrator type drum construction and controls therefor, an improved compact articulated roller, a highly'efiicient hydraulic control system and a novel steering system, all of which have independent utility.

A primary object of the invention is to provide a generally new vibratory roller compactor, small in size and flexible in application.

Another object of the invention is to provide a vibratory roller compactor characterized by ease of handling, particularly in the steering thereof.

A further object of the invention is to provide for variable operational modes of a compactor, looking toward improved soil compaction and an ability to move the compactor machine with and without accompanying vibration.

Still another object of the invention is to provide an improved hydraulic control system specially useful in units such as a roller and applicable to other work vehicles.

A still further object of the invention is to provide tandem roller drums in a vibratory roller compactor driven in unison in either direction to effect traversal of the compactor machine, and simultaneously vibrated for improved compaction, the frequency of vibration being synchronous or non-synchronous as may be found desirable by changing soil conditions.

Still another object of the invention is to provide a new and simplified power steering mechanism of general application.

An additional object of the invention is to provide structure and systems possessing the advantageous structural features, the inherent meritorious characteristics and the means and mode of operation as herein described.

With the above and other incidental objects in view as will more fully appear in the specification, the invention intended to be protected by Letters Patent consists of the features of the construction, the parts and combinations thereof, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawing wherein is shown one but obviously not necessarily the only form of embodiment of the invention,

FIG. 1 is a view in perspective of a vibratory roller compactor in accordance with the illustrated embodiment of the invention;

FIG. 2 is a view in exploded isometric of portions of the machine of FIG. 1;

FIG. 3 is a view in cross section through a roller drum assembly;

FIG. 4 is an exploded fragmentary view of a portion of the structure shown in FIG. 3;

FIG. 5 is an end view of the drum of FIG. 3;

FIG. 6 is a diagram showing the hydraulic power generating and transmitting systems;

FIG. 7 is a detail view, partly diagrammatic, of steering apparatus, showing its follow-up control;

FIG. 8 is a fragmentary elevation view of detail of the steering control on the roller superstructure;

FIG. 9 is a fragmentary plan view of machine superstructure showing operating controls;

FIG. 10 is a detail view of a spool element used in the steering control valve; and

FIG. 11 illustrates an included articulated coupling.

Referring to the drawings, a vibratory roller in accordance with the illustrated embodiment of the invention is comprised of front and rear sections 10 and 11 interconnected by an articulated coupling 12. The latter is constructed to permit the sections 10 and 11 relative swinging motion about a vertical axis and limited oscillatory motion about a horizontal axis. The machine may thus be effectively steered and in a traversal of the work may inherently accommodate to uneveness in the work surface. The structure of the coupling 12 includes, as shown in FIG. 1 l, opposing yoke-like members l3 and 14 interfitting with one another at their open ends and based at their'closed ends upon respective frame components 15 and 16. Member 14 attaches fixedly to frame component 16. Member 13 mounts rotatably, contained about a horizontally projected cylindrical stud 19 to a thrust bearing plate 17, which is in turn fixed to the frame component 15. By virtue of its mount, the member 13 is confined to bearingly seat upon bearing plate 17. The stud means 19, which may be provided by a bolt element,.provides a horizontal axis about which elements of the articulated-joint may relatively adjust. Suitable stud means interconnecting the interfltting ends of members 13 and 14 provide a vertical axis for lateral relative swinging movement of the parts.

As shown in FIG. 2, the frame component 15 is a rigid, rectangular member open between its side and end walls to position in partly enclosing relation to a roller drum assembly 21 as will hereafter more clearly appear. lt embodies angle beams 22 and 23, respectively to the rear and front thereof, the former providing at its rear center a place of attachment for the bearing plate 17 of the coupling 12. Unitarily joined to bridge the adjacent endsof the members 22 and 23, and having dependent portions, are side plates 24 and 25. At theirforeward ends the plates 24 and 25 are in projecting relation to transversely disposed member 23 and incorporate openings 26 providing a place of connection for a towed or towing means.

The frame component 16 is constructed like the component 15 to be in partly enclosing relation to a roller drum assembly 27. It includes transversely disposed end beams 28 and 29 interconnected by side plates 31 and 32, the side plates having rearwardly projecting portions incorporating openings 33 corresponding to the openings 26. The frame components occupy relatively reversed or opposing positions so that the openings 26 or 36 are available at both ends of the machine.

The framing of the machine further includes a generally rectangular formed sub frame component 37 which through dependent feet 38 seats on and is secured to theframe component 15 in a manner believed obvious from FIG. 2 of the drawings. Within its formed shape the sub frame 37 accommodates and seats a water storage tank 39. Panel members 42 and 43 mountto close the respective sides of the sub frame 37 while a cap 41 covers it top and depends to overlie forward and rearward end portions in a covering protective relation thereto and to the tank 39. An opening 44 in panel 41 allows for filling and refilling of the tank 39. In a manner which it is unnecessary here to consider; the contents of the tank 39 are suitably tapped'to allow water to trickle down upon the roller drum assembly 21 when working conditions so require;

Another formed sub frame 45 includes side segments bridged at their top by transversely disposed longitudinally spaced bars. The frame is thereby left open at its bottom and at its forward and rearward ends. The side segments have feet 46 by which the frame 45 is securely mounted on the top of the frame component 16.

Nesting in and closing the rear and a portion of the top of the frame 45 is a tank 47 providing a storage reservoir for hydraulic fluid. The sub frame 45 encloses various machine components and fixed to its top bars and projected rearwardly thereof is a longitudinally extended flat control housing 48 the details of which will be further described. v

Top panels 51 and 52 overlie the frame to either side of the control housing 48 and forwardly thereof while apertured panels 53, 54 and 55 cover the frame sides. The apertured panels have an open work construction to enable air to be drawn into and about the frame to absorb heat from circulating oil in a cooler 49.

Power for various machine operations is provided by a self-contained prime mover 56 which may be a gasoline or diesel powered engine drawing fuel from its own storage tank 57. The engine 56 is a part of the rear section'll of the machine-being carried directly by frame component 16. As shown in FIG. 11, mounting brackets 58 on the engine overlie and are connected to brackets v59 fixed to the forward bar 29 of the frame component 16. Resilient shock isolators 61 are interposed between the respective brackets, the arrangement being one in which the weight of the engine is fully supported by the frame component 16 with the latter being relieved of much of the vibratory action associated with operation of the engine. The shock isolators 61 are generally cylindrical elements made of a resilient material and having disconnected threaded means at respectively opposite ends so that threaded studs 62 and 63 extending from the engine and from the frame component may connect thereto.

Power generated by the engine 56 is converted to hydraulic pressure to achieve the desired machine operations. To this end, the engine is caused rotatably to drive a gear 64 meshing within one end of a continuous gear belt 65. The belt, inturn, accommodates in the opposite end thereof and drives a gear 66 which is on the shaft 67 of a hydraulic pump 68, the latter being in part supported by a frame mounted bracket 69. The pump 68 mounts generally in line with the oil cooler 49 and the pump shaft 67 further mounts a fan 70 disposing in such adjacent facing relation to the oil cooler that operation of the pump 68 turns the fan for a forced draft of air through the oil cooler. As will hereinafter more clearly appear, the pump 68 is connected to draw fluid from the reservoir 47 and supply it under pressure to means variously to effect propulsion or traversing movement of the machine, vibration of the roller drum assemblies 21 and 27 and steering.

The machine sections 10 and 11, in addition to being joined together by the articulated coupling 12, are interconnected by a hydraulic cylinder means 71. The

cylinder portion of such means is fixed, through a bracket 72, to the bar 28 of the'frame component 16. The piston rod portion of the cylinder means has a clevis device 73 at its outer end by which it is pivotally connected to one end of a bracket 74, this bracket being attached through a depressed offset remote end portion either directly or indirectly to the frame component of the forward machine section. In the illustrated instance, the offset end of bracket 74 is shown attached to an upwardly offset side portion of the yoke element 13 which, as seen, is rotatably connected to the frame component 15 as previously described by way of the rear bar 22. As seen, the hydraulic cylinder means 71 disposes in a substantially parallel, laterally offset relation to the major axis of articulated coupling 12. The construction and arrangement of parts accordingly is one in which the simple extension and retraction of the hydraulic piston rod means achieves angular turning movement of the forward machine section relatively to the rear section, this motion being accommodated within the coupling 12 wherein elements 13 and 14 turn relatively to one another about a vertical axis.

The roller assemblies 21 and 27 are the same so that a description of one will suffice for both. Thus, referring to FIG. 3, the roller assembly 27 includes a ground engaging cylindrical drum 75. Equally spaced inwardly from opposite open ends of the drum are respective interior wall plates 76 and 77 welded or otherwise secured in a parallel position. Wall 76 has a central through opening 78 aligning with a similar opening 79 in wall 77. A plate 81 which mounts to the wall 76 in closing relation to opening 78 has a hub portion which nests within said opening to rim the same and contains therein bearing means 82. A similar plate 83 mounts to wall 77 to contain within the opening therethrough the bearing means 84. A shaft 85 is longitudinally disposed within the drum 75 and has reduced diameter end portions rotatably mounting in bearing means 82 and 84, suitably contained against endwise movement. Weights 86 and 87 are respectively held to the periphery of shaft 85, in spaced location, by respective strap retainer devices 88 and 89. The shaft 85 is in this manner caused to be eccentrically weighted and in response to rotation thereof delivers successive forward and rearward thrusts to the drum assembly. Under relatively rapid rotation these thrusts provide well defined vibratory impusles.

To support the right hand end of the roller assembly (as viewed'in FIG. 3) there is mounted to the outer side of plate 83 a plate to which is integrated a spindle 91. The spindle 91 projects through a support plate 92 which is a rectangular member elongated in the horizontal medial plane of the roller assembly. A bearing housing 93 nested in an opening within the plate 92 closely surrounds and carries bearing means 94 for the spindle 91. A cap 95 is mounted to the housing 93 in confining relation to the bearing means 94 and the projected end of spindle 91. The dependent portions of side plates 31 and 32 of the frame component 16 are in end embracing relation to the drum 75, the plate 31 being in flanking spaced relation to the support plate 92. A plurality of shock isolators 96, preferably one at each corner of plate 92, are interposed between the support plate and the frame element 31. Screw studs 97 and 98, applied to opposite ends of the individual isolators, through the plate 92 and frame element 31 respectively, interconnect the parts. The structure and arrangement corresponds substantially to that described in connection with shock isolators 61. The roller drum assembly and the machine frame are connected and the frame 16 supported over the roller but. however, the transmission of vibratory impulses therebetween is inhibited.

At the other or left hand end of the roller assembly, shaft 85 is further extended. t projects through and beyond bearing means 82 to terminate in a reduced diameter end 99. A sleeve 101 has at one end a bore to receive shaft portion 99 and the sleeve is shrunk fit or otherwise secured to the shaft to serve as an extension thereof. Sleeve 101 is formed at its other end with an interior spline. Both the projecting end of shaft 85 and the sleeve 101, which is in effect an integral part thereof, are received in a tubular housing 103 having a flange'l04 secured by bolts 105 to the plate 81. The shaft 85 and sleeve 101 are freely rotatable within the tubular housing 103 which in turn is rotatable in bearing means 106 seated in recessed relation within a tubular segment 107 of a support member 109. A cap 108 mounts to the support member 107 in confining relation to the bearing means 106.

Referring also to FIGS. 4 and 5, the support member 109 embodying the tubular segment 107 includes plate portions 109 corresponding in function to the support plate 92 shown in FIG. 3 at the right hand end of the assembly. In substantially parallel relation to such plate portions 109 of the support member is side plate 32 of the frame component 16, a dependent portion of such side plate being in flanking spaced relation. Spacer means are provided to bridge the distance between side plate 32 and plate portions 109 to either side of the tubular segment 107. The spacer means include two transversely spaced rectangular, short width plate elements 110 and 111 separately bolted to the frame portion 32. The elements 110 and 111 are connected by respective integral perpendicularly projected web means 112 and 113 to'other corresponding plate elements 114 and 115. Disposed between the latter elements and support plate portions 109' are shock isolators 116 mounted and functioning in the same manner as shock isolators 96. Frame element 32 is accordingly in a supported relation to the support member 109 including the tubular segment 107 and plate portions 109' with, however, the transmission of vibrations therebetween being inhibited. Segment 107 is by virtue of its contained bearing means 106 and housing 103 mounted so as to form an integral part of the roller assembly.

An hydraulic motor 117 is fixedly mounted by suitable means to the support member 109. Motor 117 is a conventional commercially availableproduct and will not be described in detail. In general, it comprises rotor means turned by the flow through the motor of hydraulic pressure fluid and includes further a projecting shaft 118 aligning with shaft 85. A projecting portion of shaft 118 has a splined construction and is received within and mated with the splined portion of sleeve 101 to thereby achieve a driving relationship to the shaft 85. The supply of hydraulic fluid under pressure to the motor 117 results therefore in a rotation of shaft 118 and a corresponding rotation of the eccentrically weighted shaft 85.

The support member 109 extends upwardly from the motor 117 to terminate in a broad flat horizontally ori- 7, ented flange 121. Another hydraulic motor 122 has a base 123 seated on and bolted to the flange 121. The motor 122 is a reversible hydraulic motor of conventional construction andfunctions reversibly to rotate a projecting shaft 124 to which is fixed a small sprocket wheel 125. The wheel 125 is disposed in a common plane with a large diameter sprocket wheel 126 therebelow. The wheel 126 is secured to the flange 104 of housing 103 by means of the previously mentioned bolts 105. Accordingly, sprocket 126 is attached to and forms a part of the rotating drum components. A continuous chain 127 encircling the sprocket wheels 125 and 126 establishes a driving-driven relation therebetween so that powered rotation of the sprocket wheel 125 efi'ects corresponding rotation of the sprocket wheel 126 and thereby of the drum assembly of which it forms a part. The motor 122 is appropriately mounted to its separable base 123 for pivotal movement to adjust the slack in the drive chain 127. For this purpose, a laterally disposing plate 128 forms an integral part of the motor 122. Further, the base 123 is formed with upstanding arm portions 129 and 131 by means of which the motor is supported. Plate 128 has a projection to one side of the motor to which is pivotally attached the arm 129 through the medium of a pivot stud means 132. On the other side of the motor, a portion of plate 128 has a vertically elongated slot 133 receiving stud means 134 which projects from arm 131. An elongated screw element 135 having a threaded mounting in a portion of member 109 engages a lower edge of plate 128 directly beneath the slot 133. Screw 135, being accessible from below the support member, may be readily turned to raise and lower one side of the plate 128 to pivot the motor 122 about the stud 132. As is obvious, the raising and lowering process will vary the slack or tension in the chain 127.

As described, the roller assemblies 21 and 27 are accordingly constructed substantially to be received within, to support, and to be resiliently dependent from their respective frame components and 16 and to be operable independently thereof in rotary and vibratory senses. in accordance with the invention, moveover, each roller assembly is subject to independent rotary drive and vibration, each having what may be termed its own traverse motor 122 for driving purposes and a motor 117 for purposes of controlling its vibration. As will be seen, each has its own hydraulic connections so that traverse and vibration of the drum may be carried out conjointly or the vibratory impulses selectively discontinued, as may be desirable in some classes of work'or in moving the machine from one working site to another.

The several motors 117 and 122 are in a hydraulic system along with the hydraulic actuating cylinder 71, pump 68, oil cooler 49, reservoir 47 and various frame mounted valve devices, all as diagrammatically indicated in FIG. 6. As there shown, the operation of pump 68, resulting from energizing of the prime mover, draws oil from reservoir 47, by way of a supply line 130, and forces it under pressure through three outlet conductors 136, 137 and 138. The conductor 136 supplies pressure fluid to the drive or traverse circuit by way of a main control valve 139. The latter is suitably constructed to direct incoming pressure fluid alternatively through outlet lines 141 and 142 which in turn lead to a dual over-center valve 143. From the latter a line 144 leads to one side of the high speed, low torque, motor 122 in roller assembly 21 while a line 145 leads to an opposite side of the similar motor 122 in assembly 27. Other sides of the respective motors 122 are interconnected by a line l46. lf valve 139 is set to direct pressure fluid from the pump to outlet line 141, the flow is through line 141 to and through the valve 143 and through line 144 to the motor 122 in roller assembly 21. From this pump the oil flows through cross connection 146 to motor 122 in the roller assembly 27, effecting thereby a simultaneous drive of both motors and in the same direction. Upon leaving the second encountered motor 122, the'pressure fluid returns by way of line 145 to and through valve. 143 and back to valve 139 by way of line 142. Within valve 139, the returning fluid is directed byway of a return line 147 to the reservoir 47, there being interposed in the return line the oil cooler 49, a manifold 148 and an oil filter 149. A reverse drive is achieved by setting the valve 139 to direct fluid received from pump 68 to outlet line 142, whereupon the direction of flow is the reverse of that previously described with the pressure fluid going first to the motor 122 in roller assembly 27 and subsequently to the motor 122 in roller assembly 21 before returning to the main control valve and being directed to the reservoir. It will be evident that as a result of such reversal of flow the direction of rotation of the motors 122 is reversed and the applied rotary drive to the roller assemblies is reversed. The dual over-center valve 143 preventsthe motors 122 from running ahead of the pump when operating the roller on down grades. If the motors try to run ahead of the pump, relief means in the valve 143 throttles the pressure fluid flow in direct proportion to the setting of the valve 139 and will prevent a free wheeling condition. Both valves 139 and 143 are conventional commercially obtainable components and will not be further described except that controls to operate valve 139 will hereinafter be pointed out.

Pump outlet conductor 137 supplies the vibrator motors 117. It leads from an outlet of the pump different from that supplying line 136, through a speed selector valve 151, to a line l52 in which is an on-off control valve 153. From valve 153 a line 154 leads to a flow divider valve 155 from which extends a line 156 leading to the motor 117 in roller assembly 21 and another line 157 leading to the motor 117 .in roller assembly 27. From the motor 117 in roller assembly 21 a return flow line 158 extends to manifold 148 and so communicates with reservoir 47. In the flow line 158 is one-way valve means 159. From the motor 117 in roller assembly 27 a return line 161 communicates with line 158 in advance of one-way valve 159. The on-off valve 153 has another outlet line 162 leading directly to manifold 148. With control valve 153 set to an on" position, incoming pressure fluid is directed to line 154 and splits at flow divider 155 .to effect simultaneous operation of the motors 117, the flowing oil returning to the reservoir by way of the described lines 158 and 161. With the selector valve set to an off position flow out of the valve is switched to outlet line 1.62 where it returns directly to reservoir 47 without passing through the circuit. For control of valve 151 to achieve selective operation or by pass of the vibrator motors 117, internal valve means may be operated by an externally accessible plunger 151' adapted to be pulled out and to be pushed in to effect alternate modes of operation. In a first mode the pressure fluid supplied by conductor 137 is directed exclusively or substantially so to line 152 and so supplies the vibrator circuit. In a second mode, flow to line 152 is cut off and all of the incoming pressure fluid or substantially all thereof which is normally directed to motors 117 is directed by way of by-pass line 163 into the traverse circuit. The result is a combination of augmenting the flow to the traverse circuit with a discontinuing of flow to the vibrator circuit whereby to create a pressured fluid flow by means of which the motors 122 can be driven at high speed and the machine can be moved under relatively rapid travel conditions from one working site to another, with vibratory action in the roller assemblies being suppressed.

Pump outlet 138 leads to a control valve 164 from which extend lines 165 and 166 leading to opposite ends of the hydraulic cylinder 71 and a line 167 leading to manifold 148. Valve 164 is a four-way valve assembly and in accordance with the known mode of operation of such elements an interior valve element, as device 168 in FIG. 10, occupies a neutral position in which all in-comming flow from conductor 138 is directed to manifold 148 and thereby to reservoir 47. The valve element is shiftable in opposite senses from its neutral position to direct in-coming fluid either through line 165 or line 166 in a manner selectively to effect extending or retracting movements of the hydraulic piston rod with its attached clevis 73. Actuation of the hydraulic cylinder in either direction forces hydraulic fluid out of the cylinder ahead of the extending or retracting piston, initiating a return flow through the non-selected line 165 or 166. Such return flow within the valve assembly 164 is directed to outlet line 167 and returned to the reservoir. The element 168 is a spool type valve element having spaced cylindrical lands 169 and a reduced diameter stem portion 171 by which axial adjustment of the spool-like element 'may be effected. Certain of the cylindrical lands 169 are relieved or chamfered at selected ends. This relieves return flow load holding characteristics and insures that the opening or return flow from the hydraulic cylinder 71 occurs slightly ahead of cylinder pressurization. This imparts a very smooth action to the overall steering function.

As shown in FIGS. 8 and 9, previously mentioned control housing 48 comprises a bracket 172 of U-like cross-sectional configuration fastened to the sub frame component 45. Rearwardly extending and convergent bars 173 are attached to and project from bracket 172 and are overlaid by a panel 174. Near the outer end of the control housing a transverse shaft 175 is mounted, to which is secured an upstanding handle 176 projecting upward through an opening 177 in the panel 174. Pivotally attached to the handle 176, at a location spaced above shaft 175, is a rod assembly 178 extending forwardly in the control housing and attaching by a right angled forward extremity to a vertically oriented arm 179. The latter pivotally attaches to a bracket 181 mounted to form a part of the traverse valve control unit 139. The valve unit 139 mounts to the underside of bracket 172 and, in a manner the details of which it is unnecessary here to consider, responds to certain pivoting movement of the arm 179, through conventional control elements thereof, to direct flow, selectively, to outlet lines 141 and 142 as previously discussed. ln the illustrated instance, an upright position of the handle 176 as shown identifies a neutral setting of the valve controls whereby the output from pump 68 is channeled directly to return line 147 and thence to the reservoir. No power under these circumstances is transmitted to the roller assemblies 21 and 27. Moving the handle 176 forwardly from its neutral position connects the return flow line 147 to the valve output line 142 and directs the fluid pressure in-coming from pump 68 to line 141. in the manner previously discussed, therefore, flow to the motors 122 occurs in such direction as to effect a forward travel of the machine, with the circulating fluid returning to valve 139 by way of line and being conducted by line 147 to the reservoir. Motors 122 are high torque, low speed motors rejecting substantial amounts of heat to the circulating fluid, which heat is removed in the cooler 49. Movement of the handle 176 to the rear from its neutral position has a reverse effect, producing an opposite direction of rotation of the roller assemblies and a reverse travel of the machine. For safety purposes, a torsion spring 182 is wrapped around shaft and so anchored as to urge handle 176 to the upright position illustrated. This so-called Dead-man control insures that the control handle cannot inadvertently be left in a reverse operating position.

As indicated in FIGS. 1 and 2, the vibrator control valve 153 is mounted to the underside of sub frame means 45 and includes an operating handle 183 projecting upward through an opening defined by the uppermost panel means 51-52. As seen heretofore, valve 153 is essentially an on-off control in which the fluid output of pump 68 directed to such valve is in turn directed either to vibrator motors 117 or to the reservoir 47. Operating handle 183 is moved forwardly and rearwardly to alternate control positions to effect the described operations.

The speed control valve 151 mounts in the control housing 48 near the front thereof, being dependent frombracket means 184 supported from the rigid assembly of bars 173. Plunger 151' extends through an opening in panel 174 and is accessible for the push-pull operation previously described.

From the open outer end of the control housing 48 projects a handle 184 to the outer extremity of which is fixed a cross member 185. Within the control housing the inner end of handle 184 is attached to a sleeve 186 pivotally mounted on a stud 187 mounted in a bracket assembly 188 secured between the tapering bars 173. Projecting laterally from the sleeve 186 is a rigidly attached arm 189 pivotally attached to rod assembly 191. The rod assembly 191 includes parts one end 194 of one of which is telescopically nested in a sleeve forming the rear extension of the other. The end 194 has a piston-like head. Confined within the sleeve to each of opposite sides of the head is a coil spring S or S as shown in the drawings. The assembly extends forwardly in the machine through and beyond the opposite end of the control housing where if joins unitarily to a Bowden type wire cable 192 housed in a sheath 193. One end of the sheath 193 is fixed in a fitting 195 and so, at what may be considered its inner end, it is secured to the rear machine section 11. Cable 192 is relatively reciprocable in sheath 193 and a rotating movement of the handle 184 will accordingly have the effect, through rod means 191, of extending and retracting the cable within its sheath. Such movements of the handle 184 are used as in-put signals to effect power steering of the front machine section 10.

The assembly of cable 192 and its sheath 193 projects forwardly and downwardly in the machine. and, as shown more particularly in the diagram of FIG. 7, is reversed in direction to describe a loop 196 before reaching selector valve 164 which it controls. Valve 164 is mounted to a projecting tab 190 on the front bar 29 of frame component 16. in the course of describing its loop 196, the cable 192 and its sheath extend to and reversely from the forward machine section, with the outer end of the sheath portion 193 being suitably 'secured thereto. As diagrammatically shown in FIG. 7, the yoke-like part 13 of the articulated coupling 12 has an integral laterally offset portion 197. Sheath 193 terminates in a collar 198 which is suitably fastened to the offset portion 197 at an intermediate location thereof. At its outer end, portion 197 is pivotally connected to clevis 73 projected from hydraulic cylinder 71. The point of attachment of the collar 198 to offset portion 197 accordingly is between the joint of the articulated coupling and the location where extending and retracting movements of the cylinder 71 are applied.

The core wire 192 extends freely from the outer end of sheath 193 and projects into the valve unit 164 where it is suitably connected to achieve an operative connected relation to stem 171 of the spool element 168. Relative projecting and retracting movements of the wire cable effect corresponding movements of the spool element 168 and cause fluid to flow selectively to opposite ends of thecylinder. By the construction provided, the steering apparatus is inherently self canceling in its control over flowing pressure fluid so that effected angular turning movements of thefront machine section will correspond to and be limited to the amount of turning motion imparted to handle 184.

In the valve assembly tends normally to occupy a neutral position in which flow from the pump enters the valve assembly by way of an inlet 199 and is routed directly back to the reser-' voir by way of an outlet 201. Outlets 202 and 203 leading respectively to the front and rear of the cylinder 71 r are at this time closed, with flow to and from the cylinder by these routes being blocked. A motion of the cable 192 to withdraw the same relative valve unit 164 moves spool element 168 within the valve assembly to cause in-coming fluid at port 199 to flow to outlet port 202 and thence to the front of cylinder 71 where it effects a retracting movement of the piston rod and turns the front machine section angularly in a clockwise direction as viewed in F IG. 7 or to the right. At the same time outlet port 203 is connected to reservoir return port 201 and fluid within the cylinder tending to be trapped behind the retracting piston therein escapes by way of port 201 back to the reservoir. A similar but reverse mode of operation takes place in the event of projection of the cable 192, with inlet port 199 being at this time connected to outlet port 203 and outlet port 202 being connected to reservoir port 201. In such cases the piston rod is projected to turn the front machine section to the left or counter-clockwise. in order that the amount of movement permitted the front machine section may correspond to and be limited to the 1.64 the spool element 168 extent of the in-put signal as represented by the amount of turning motion given handle 184, spool 168 is inherently and automatically readjusted to a neutral position in response to the effected angular steering movement of the front section. Thus, in a movement of the spool, effecting a clockwise direction of rotation of the front machine section, the loop 196 is shortened to carry the cable 192 and its sheath 193 bodily rearward. The wire cable 192 reacts to this movement to restore the spool element 168 to its neutral position. The parts are accordingly hydraulically locked in the position to which they have been set by movement of the handle 184 and will remain so positioned until the handle 184 is moved additionally in a control sense or is returned to a normal centrally located position. Similarly, in an opposite movement of the spool wherein wire 192 is moved to produce a resulting counterclockwise movement of the front machine section, the latter acts oppositely on the core'wire and provides that the spool element 168 reassumes a neutral position, hydraulically locking the cylinder 71 in position as before described. Thus, as handle 184 is rocked to a selected position the front machine section will move correspondingly and oppositely and in proportion thereto and the machine section will maintain its adjusted position as long as the control handle is held so adjusted and will move additionally or will return to a normal straight position all in accordance within-put signals as received from the control handle assembly. The front end section of the machine has been described as operating in certain directions in response to certain turning motions of the handle 184. It will be understood that the direction in which the machine steers in response to movements imparted to the control handle may be selected by making appropriate connections. It is noted that the springs embodied in rod assembly 191 insure a smooth acting response of the wire or cable 192 to movement of the control handle.

The severalcontrols for the machine, including steeringhandle 184, traverse handle 176, vibrator handle 1 83 and speed selector plunger 151 are accordingly all positioned at the rear of the machine conveniently accessible to an operator. The operator will usually walk behind the machine, holding with both hands to the cross member of the steering handle, with the other controls being conveniently I available when needed. The machine responds relatively sensitively to steering impulses and it will be understood in this connection that movement of the steering handle requires no particular strength, the provided power steering greatly relieving the fatigue normally associated with operation of machines of this kind. The handle 176 is moved in either forward or reverse directions with corresponding efi'ect upon the-direction of movement of the machine and the vibrator handle 183 is adjusted to on-off positions in accordance with the need for or lack of need for vibration in the work under way. The speed selector plunger 151' will normally be adjusted inward whereby the machine moves at a norrnaLlow speed with vibration being solely under control of the handle 183. However, in moving from one working site to another the operator can elect to pull plunger 151' out- 'ward, in which operational mode vibration is suppressed and hydraulic flow to the traverse motors augmented with consequent greater speed of movement of the machine.

The machine is adapted for asphalt finishing as well as for the compaction of soil, gravel and the like. In this connection, the control housing 48 provides an elevated broad surface which may be used to mount a seat to convert the machine to a riding vehicle. Steering handle 184 may in this mode of operation be conveniently operated by adapter means while the other controls remain readily accessible to the hand of the operator.

Scraper bars 204 and 205 extend transversely of respective roller assemblies 21 and 27 externally thereof so that the drums 75 may in use by self-cleaning. The scraper bars attach at their ends to respective bracket members 206 and 207 anchored respectively to the support plate 92 and the support member 109.

The hydraulic fluid conducting lines are shown in the drawing as having a rigid, pipe-like form. However, at least in the case of those lines leading to the vibrator motors 117 and to the traverse motors 122, these lines are in the form of hose type connectors sufficiently strong to contain applied fluid pressures but flexible to accommodate vibratory movement of the roller assemblies relative to the machine frame. For example, and referring to FIG. 9, traverse control valve 139 has installed therein a plurality of threaded connectors 208. The several hydraulic flow lines 136, 141, 142 and 147 attach to the individual threaded connectors, and, as indicated, have a reinforced rubber or rubber-like construction to be relatively strong but to flex in the presence of applied vibratory impulses. Similarly, in the case of valve 151, integrated connectors 209 provide places of attachment for hose type conductors defining the lines 137, 152 and 163. Lines 144 and 145 extending from valve 143 to the traverse motors and other lines extending from valve 153 to the vibrator motors are similarly attached and constructed to conduct hydraulic pressure in the presence of machine vibration.

The use of a vibrator motor at each roller assembly enables a vibratory rate to be selected, and, if desired, enables a differential selection as between the forward and rear assemblies. For such purposes suitable controls may be included to selectively differentiate in flow to the respective motors 117 by way of the divider valve described.

In a typical embodiment of considerable advantage in soil compaction for example, the rate of vibration at the forward roller assembly may be made to be 3400 vibrations per minute, while the rate at the rear is made to be 2600 vibrations per minute. In such particular work, the forward assembly vibrates at approximately the third harmonic of the soils natural frequency, while vibration at the rear is approximately double the natural frequency. The built in amplification factor selected lends a capability of particalizing the soil for better soil compaction. The utilizing of both higher and lower vibration frequencies assures maximum results in connection with both larger and smaller size soil components in compacting applications and such procedure is significantly within the scope of the present invention.

From the preceding it will be obvious that the invention has produced unique structural concepts in vibrating type roller units and controls therefor as well as a greatly improved compact articulated roller assembly which is more efficient and satisfactory in use and easy to maintain. Moreover, the hydraulic controls and steering system of the invention are per se significant in their effect. particularly in the earth working machine art.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible to modification in its form, proportions, detail construction and arrangement of parts without departing from the principles involved or sacrificing any of their advantage.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise but one of several modes of putting the invention into effect and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

We claim:

l. A ground traversing machine. including a frame having a prime mover thereon, at least one ground en gaging roller drum, shaft means within and mounting said drum thereon with freedom of relative rotary motion, means supporting the assembly comprising said shaft means and said drum from said frame for relative vibratory and rotary motions, said supporting means including a support member mounted to said frame in shock isolated relation thereto and means fixed to said drum relatively rotatably receiving a projecting end of said shaft means and having a rotary bearing in said support member, an eccentric load on said shaft means in said drum, and means powered from said prime mover to rotate said shaft means.

2. A machine according to claim 1, characterized by other means powered from said prime mover to rotate said roller drum, the said means powered from said prime mover cooperating to achieve traversal of the machine over ground surface with simultaneous drum vibration.

3. Apparatus as set forth in claim 1 characterized by said support member mounting thereon a motor means drivingly coupled to means in connection with said drum for rotation thereof.

4. A machine as in claim 3 characterized by said means to rotate said shaft means including a shaft drive motor, which motor and said motor means in connection with said drum for rotation thereof are independently operable but hydraulically connected so their motive power derives from a common source.

5. A machine according to claim 2 wherein said frame is comprised of a pair of frame components substantially in line with one another and interconnected in an articulated relation. an assembly comprising said roller drum and said shaft means mounting said drum being associated with each of said frame components, and said other means powered from said prime mover to rotate said roller drum comprising means defining a hydraulic circuit including a motor in direct association with each drum, said drum motors being in a series relation in said circuit which includes means to reversibly flow pressure fluid through said circuit to said motors for a simultaneous drive of said drums through the medium thereof in either a forward or a reverse direction.

6. A machine according to claim 2 wherein said frame is comprised of articulated frame components, at least two said frame components each suspending therefrom a separate assembly comprising said roller drum and said shaft means, with additional means powered from said prime mover being arranged to connect with and turn one drum in steering movements and means located at and projected from one of said frame components conveniently accessible to an operator walking behind or sitting on said machine having in connection therewith means for selectively conjointly or separately initiating, modifying and discontinuing machine movement, steering and drum vibration.

7. A machine according to claim 2 characterized in that said frame is comprised of articulated frame components, at least two of said frame components each suspending therefrom a separate assembly comprising said roller drum and said shaft means, each said shaft' means having in connection therewith separate motor means for drive thereof and each said drum having in connection therewith separate motor means for drive thereof and a common source of motive power to drivesaid motor means having in connection therewith means for reversibly driving the motor means driving said drums, said last named means including a speed control effective in either direction of rotation of said drums.

8. A machine as in claim 7 characterized by means for selectively disabling the motor means for driving said shaft means.

9. A machine as in claim 8 characterized by means for dividing the motive power delivered to drive said shaft means.

10. A ground traversing machine, including a frame ground surface with simultaneous drum. vibration,

means comprised in the means to rotate the shaft means and operable independently of the prime mover selectively operable to divert the power supplied to rotate said shaft means to achieve an augmented powering of the means to rotate said roller drum whereby the machine may without prime mover adjustment selectively be conditioned for relatively rapid traversal without drum vibration.

11. A machine according to claim 10, wherein said other means includes a hydraulic circuit, characterized by control means settable independently of said selectively operable means to reverse the direction of flow in said circuit whereby selectively to achieve forward and reverse traversal of the machine.

12. A ground traversing machine, including a frame having a prime mover thereon'and being comprised of articulated frame components, there being at least two of said frame components each suspending therefrom a separate assembly comprising a roller drum and shaft means, the latter mounting said drum thereon with freedom of relative rotary motion, an eccentric load on said shaft means in each said drum, means po'wered from said prime mover to rotate said shaft means, the means suspending said assembly from at least one of the two said frame components incorporating resilient shock isolating elements in the connection between the frame component and said assembly, the two said frame components being longitudinally spaced from one another and interconnected by an articulated joint. the said one of the two frame components occupying a position forwardly of the other having regard to the normal direction of movement of the machine,'and means for steering the machine including a linkage extending between and interconnecting said two frame components disposing in a laterally offset relation to said articulated joint and being operable to effect turning movements of said one frame component relative the other, said linkage embodying a hydraulic cylinder including aprojected rod the extension or retraction of which provides corresponding direct turning movement'of said one frame component,-said hydraulic cylinder being in a hydraulic circuit further comprising a source of hydraulic fluid under pressure and valve means positionable to direct pressure fluid to alternate ends of said cylinder and means to operate said valve means including input means arranged for movement of said valve from a neutral position and there being means included in said input means to produce a follow-up control responsive to the applied turning movement of said one frame component to position said valve means in neutral whereby to hold the so-adjusted position of said frame component.

13.. A machine according to claim 12 wherein said input means includes a cable subject at one end to push-pull impulses and operatively related at its other end to said valve means, and includes further a sheath for said cable connected at opposite ends to said frame components, the assembly comprising said cable and sheath incorporating a loop in advance of said valve inherently foreshortened and lengthened by opposite turning movements of said one frame component to provide said follow-up control.

14. A machine according to claim 13 wherein said sheath attaches at its one end to said one frame component at a location intermediate said articulated joint and a point of connection of a portion of said hydraulic cylinder unit to said one frame component.

15. A work machine comprising an articulated frame,

a prime mover on said frame, articulated sections of which respectively mount ground engaging vmeans embodying therein vibrator means, individual motors activating the movement of said ground engaging means, individual motors for. actuating said vibrator means and means for selectively actuating said motors independent of said prime'mover to provide directional and speed control of said ground engaging means and onoff control of said vibrator means.

16. Apparatus as set forth in claim 15 characterized by means providing a common source of fluid power for driving said motors, means for selectively directing fluid to said motors for said ground engaging means to optionally dictate the nature of their movement on activation thereof, means for selectively directing the flow of fluid to said vibrator motors and for selectively bypassing the flow in respect thereto and one of said means for directing fluid including speed selector control means.

17. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, means to effect rotary drive of said drum, other means to effect vibration of said drum, said means being embodied in a hydraulic control system in connection with said prime mover and including means for directing hydraulic fluid in separate streams to simultaneously effect the vibration and rotary drive of said drum, and other means, independent of said prime mover, for diverting at least a portion of the stream directed to effect vibration of said drum to the stream for effecting rotary drive of said drum to produce a rotary drive of said drum without vibration or adjustment of said prime mover which is at a higher speed than when driven and simultaneously vibrated,

18. A machine according to claim 17 wherein the said diverting means includes control valve means having alternate positions of adjustment in one of which hydraulic fluid is directed to influence vibration of said drum and in another of which at least a portion of the hydraulic fluid directed to influence vibration of said drum is redirected to augment the hydraulic fluid directed to influence rotary drive of said drum.

19. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, shaft means within and mounting said drum thereon with freedom of relative rotary motion, means supporting the assembly comprising said shaft means and said drum from said frame for relative vibratory and rotary motions, said supporting means including a support member mounted to said frame in shock isolated relation thereto and a tubular housing fixed to said drum, said tubular housing relatively rotatably receiving a projecting end of said shaft means and having a rotary bearing in said support member, an eccentric load on said shaft means in said drum, means powered from said prime mover to rotate said shaft means, said means powered from said prime mover being a hydraulic means, and other hydraulic means powered from said prime mover to rotate said drum, the one said hydraulic means and the said other hydraulic means respectively including a motor mounted on said support member, one of said motors being operable to rotate said shaft means and the other to rotate said drum through said tubular housing.

20. A machine according to claim 19, wherein one of said motors is mounted for access to said shaft means through an open end of said tubular housing, said tubular housing having external gear means thereon for drive thereof from the other of said motors.

21. A ground traversing machine, including a frame, a prime mover on said frame including means for supplying hydraulic fluid under pressure, at least one ground engaging roller drum in connection with said frame, a traverse circuit including means to direct hydraulic fluid furnished by said supply means to effect rotary drive of said drum, a vibratory circuit including other means to direct hydraulic fluid furnished by said supply means to effect vibration of said drum, and speed control means in connection with said vibratory circuit adjustable independent of said prime mover to effect different modes of operating said machine in a first of which said drum is simultaneously driven and vibrated and in another of which said drum is rotatively driven at a speed higher than in the first said mode and is not vibrated, said speed control being a valve having alternative positions of adjustment in one of which it permits flow through said vibratory curcuit and in the other of which it denies flow through said vibratory circuit and diverts the hydraulic flow directed thereto to said traverse circuit.

22. A work machine comprising an articulated frame, articulated sections of which respectively mount ground engaging means embodying therein vibrator means, individual motors for activating the movement of said ground engaging means, individual motors for actuating said vibrator means, means for independently and selectively actuating said motors to provide directional and speed control of said ground engaging means and on-off control of said vibrator means, said means for independently and selectively actuating said motors including means providing a common source of fluid power for driving said motors, means for selectively directing fluid to said motors for said ground engaging means to optionally dictate the nature of their movement on activation thereof, and means for selectively directing the flow of fluid to said vibrator motors and for selectively by-passing the flow in respect thereto, one of said means for directing fluid including speed selector control means, the said means for directing the flow of fluid to said vibrator motors including means selectively dividing the flow to such motors.

23. A ground traversing machine, including a frame, a prime mover on said frame including means for supplying hydraulic fluid under pressure, at least one ground engaging roller drum in connection with said frame, a traverse circuit including means to direct hydraulic fluid furnished by said supply means to effect rotary drive of said drum, a vibrating circuit including other means to direct hydraulic fluid furnished by said supply means to effect vibration of said drum, :1 speed control valve in connection with said vibratory circuit adjustable to effect different modes of operating said machine in a first of which said drum is simultaneously driven and vibrated and in another of which said drum is rotatively driven at a speed higher than in the first said mode and is not vibrated, said valve having alternative positions of adjustment in one of which it permits flow through said vibratory circuit and in the other. of which it denies flow through said vibratory circuit and diverts the hydraulic flow directed thereto to said traverse circuit, and another valve in connection with said vibratory circuit downstream of said speed control valve in reference to the direction of hydraulic flow settable to render said vibratory circuit alternatively effective and ineffective to vibrate said drum irrespective of the position of adjustment of said speed control valve.

24. A ground traversing machine, including a frame having a prime mover thereon, at least one rotatable ground engaging means, means supporting said rotatable ground engaging means from said frame for relative vibratory and rotary motions, means powered from said prime mover to rotate said rotatable ground engaging means, other means powered from said prime mover to vibrate said rotatable ground engaging means, the said means powered from said prime mover cooperating to achieve traversal of the machine over ground surface with simultaneous drum vibration, speed control means selectively adjustable to divert the power supplied to vibrate said rotatable ground engaging means to achieve an augmented powering of the means to rotate said rotatable ground engaging means whereby the machine may selectively be conditioned for relatively rapid traversal without drum vibration, and other means settable to render said means to vibrate said rotatable ground engaging means alternatively effective and ineffective irrespective of the position of adjustment of said speed control means.

Patent No. 3,814,531 Dated June 4, 1974 Inventor(s) John I. Carnahan and Eugene C. Briggs It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 48, "impusles" is corrected to read impulses Column 6, line 3;, "t" is corrected to read It Column 6, line 27, "109" is corrected to read 109' Column 13, line 12, "by" is corrected to read be Signed and sealed this 29th day of October 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. C. MARSHALL DANN Att'esting Officer Commissioner of Patents FORM PC4050 (w'sg) USCOMM-DC 6O376-P69 11.5. GOVERNMENT PRINTING OFFICE 1 1569 356'33 

1. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, shaft means within and mounting said drum thereon with freedom of relative rotary motion, means supporting the assembly comprising said shaft means and said drum from said frame for relative vibratory and rotary motions, said supporting means including a support member mounted to said frame in shock isolated relation thereto and means fixed to said drum relatively rotatably receiving a projecting end of Said shaft means and having a rotary bearing in said support member, an eccentric load on said shaft means in said drum, and means powered from said prime mover to rotate said shaft means.
 2. A machine according to claim 1, characterized by other means powered from said prime mover to rotate said roller drum, the said means powered from said prime mover cooperating to achieve traversal of the machine over ground surface with simultaneous drum vibration.
 3. Apparatus as set forth in claim 1 characterized by said support member mounting thereon a motor means drivingly coupled to means in connection with said drum for rotation thereof.
 4. A machine as in claim 3 characterized by said means to rotate said shaft means including a shaft drive motor, which motor and said motor means in connection with said drum for rotation thereof are independently operable but hydraulically connected so their motive power derives from a common source.
 5. A machine according to claim 2 wherein said frame is comprised of a pair of frame components substantially in line with one another and interconnected in an articulated relation, an assembly comprising said roller drum and said shaft means mounting said drum being associated with each of said frame components, and said other means powered from said prime mover to rotate said roller drum comprising means defining a hydraulic circuit including a motor in direct association with each drum, said drum motors being in a series relation in said circuit which includes means to reversibly flow pressure fluid through said circuit to said motors for a simultaneous drive of said drums through the medium thereof in either a forward or a reverse direction.
 6. A machine according to claim 2 wherein said frame is comprised of articulated frame components, at least two said frame components each suspending therefrom a separate assembly comprising said roller drum and said shaft means, with additional means powered from said prime mover being arranged to connect with and turn one drum in steering movements and means located at and projected from one of said frame components conveniently accessible to an operator walking behind or sitting on said machine having in connection therewith means for selectively conjointly or separately initiating, modifying and discontinuing machine movement, steering and drum vibration.
 7. A machine according to claim 2 characterized in that said frame is comprised of articulated frame components, at least two of said frame components each suspending therefrom a separate assembly comprising said roller drum and said shaft means, each said shaft means having in connection therewith separate motor means for drive thereof and each said drum having in connection therewith separate motor means for drive thereof and a common source of motive power to drive said motor means having in connection therewith means for reversibly driving the motor means driving said drums, said last named means including a speed control effective in either direction of rotation of said drums.
 8. A machine as in claim 7 characterized by means for selectively disabling the motor means for driving said shaft means.
 9. A machine as in claim 8 characterized by means for dividing the motive power delivered to drive said shaft means.
 10. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, shaft means within and mounting said drum thereon with freedom of relative rotary motion, means supporting the assembly comprising said shaft means and said drum from said frame for relative vibratory and rotary motions, an eccentric load on said shaft means in said drum, means powered from said prime mover to rotate the shaft means, other means powered from said prime mover to rotate said roller drum, the said means powered from said prime mover cooperating to achieve traversal of the machine over ground surface with simultaneous drum vibration, means comprised in tHe means to rotate the shaft means and operable independently of the prime mover selectively operable to divert the power supplied to rotate said shaft means to achieve an augmented powering of the means to rotate said roller drum whereby the machine may without prime mover adjustment selectively be conditioned for relatively rapid traversal without drum vibration.
 11. A machine according to claim 10, wherein said other means includes a hydraulic circuit, characterized by control means settable independently of said selectively operable means to reverse the direction of flow in said circuit whereby selectively to achieve forward and reverse traversal of the machine.
 12. A ground traversing machine, including a frame having a prime mover thereon and being comprised of articulated frame components, there being at least two of said frame components each suspending therefrom a separate assembly comprising a roller drum and shaft means, the latter mounting said drum thereon with freedom of relative rotary motion, an eccentric load on said shaft means in each said drum, means powered from said prime mover to rotate said shaft means, the means suspending said assembly from at least one of the two said frame components incorporating resilient shock isolating elements in the connection between the frame component and said assembly, the two said frame components being longitudinally spaced from one another and interconnected by an articulated joint, the said one of the two frame components occupying a position forwardly of the other having regard to the normal direction of movement of the machine, and means for steering the machine including a linkage extending between and interconnecting said two frame components disposing in a laterally offset relation to said articulated joint and being operable to effect turning movements of said one frame component relative the other, said linkage embodying a hydraulic cylinder including a projected rod the extension or retraction of which provides corresponding direct turning movement of said one frame component, said hydraulic cylinder being in a hydraulic circuit further comprising a source of hydraulic fluid under pressure and valve means positionable to direct pressure fluid to alternate ends of said cylinder and means to operate said valve means including input means arranged for movement of said valve from a neutral position and there being means included in said input means to produce a follow-up control responsive to the applied turning movement of said one frame component to position said valve means in neutral whereby to hold the so-adjusted position of said frame component.
 13. A machine according to claim 12 wherein said input means includes a cable subject at one end to push-pull impulses and operatively related at its other end to said valve means, and includes further a sheath for said cable connected at opposite ends to said frame components, the assembly comprising said cable and sheath incorporating a loop in advance of said valve inherently foreshortened and lengthened by opposite turning movements of said one frame component to provide said follow-up control.
 14. A machine according to claim 13 wherein said sheath attaches at its one end to said one frame component at a location intermediate said articulated joint and a point of connection of a portion of said hydraulic cylinder unit to said one frame component.
 15. A work machine comprising an articulated frame, a prime mover on said frame, articulated sections of which respectively mount ground engaging means embodying therein vibrator means, individual motors activating the movement of said ground engaging means, individual motors for actuating said vibrator means and means for selectively actuating said motors independent of said prime mover to provide directional and speed control of said ground engaging means and on-off control of said vibrator means.
 16. Apparatus as set forth in claim 15 characterized by means providing a common source Of fluid power for driving said motors, means for selectively directing fluid to said motors for said ground engaging means to optionally dictate the nature of their movement on activation thereof, means for selectively directing the flow of fluid to said vibrator motors and for selectively by-passing the flow in respect thereto and one of said means for directing fluid including speed selector control means.
 17. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, means to effect rotary drive of said drum, other means to effect vibration of said drum, said means being embodied in a hydraulic control system in connection with said prime mover and including means for directing hydraulic fluid in separate streams to simultaneously effect the vibration and rotary drive of said drum, and other means, independent of said prime mover, for diverting at least a portion of the stream directed to effect vibration of said drum to the stream for effecting rotary drive of said drum to produce a rotary drive of said drum without vibration or adjustment of said prime mover which is at a higher speed than when driven and simultaneously vibrated.
 18. A machine according to claim 17 wherein the said diverting means includes control valve means having alternate positions of adjustment in one of which hydraulic fluid is directed to influence vibration of said drum and in another of which at least a portion of the hydraulic fluid directed to influence vibration of said drum is redirected to augment the hydraulic fluid directed to influence rotary drive of said drum.
 19. A ground traversing machine, including a frame having a prime mover thereon, at least one ground engaging roller drum, shaft means within and mounting said drum thereon with freedom of relative rotary motion, means supporting the assembly comprising said shaft means and said drum from said frame for relative vibratory and rotary motions, said supporting means including a support member mounted to said frame in shock isolated relation thereto and a tubular housing fixed to said drum, said tubular housing relatively rotatably receiving a projecting end of said shaft means and having a rotary bearing in said support member, an eccentric load on said shaft means in said drum, means powered from said prime mover to rotate said shaft means, said means powered from said prime mover being a hydraulic means, and other hydraulic means powered from said prime mover to rotate said drum, the one said hydraulic means and the said other hydraulic means respectively including a motor mounted on said support member, one of said motors being operable to rotate said shaft means and the other to rotate said drum through said tubular housing.
 20. A machine according to claim 19, wherein one of said motors is mounted for access to said shaft means through an open end of said tubular housing, said tubular housing having external gear means thereon for drive thereof from the other of said motors.
 21. A ground traversing machine, including a frame, a prime mover on said frame including means for supplying hydraulic fluid under pressure, at least one ground engaging roller drum in connection with said frame, a traverse circuit including means to direct hydraulic fluid furnished by said supply means to effect rotary drive of said drum, a vibratory circuit including other means to direct hydraulic fluid furnished by said supply means to effect vibration of said drum, and speed control means in connection with said vibratory circuit adjustable independent of said prime mover to effect different modes of operating said machine in a first of which said drum is simultaneously driven and vibrated and in another of which said drum is rotatively driven at a speed higher than in the first said mode and is not vibrated, said speed control being a valve having alternative positions of adjustment in one of which it permits flow through said vibratory curcuit and in thE other of which it denies flow through said vibratory circuit and diverts the hydraulic flow directed thereto to said traverse circuit.
 22. A work machine comprising an articulated frame, articulated sections of which respectively mount ground engaging means embodying therein vibrator means, individual motors for activating the movement of said ground engaging means, individual motors for actuating said vibrator means, means for independently and selectively actuating said motors to provide directional and speed control of said ground engaging means and on-off control of said vibrator means, said means for independently and selectively actuating said motors including means providing a common source of fluid power for driving said motors, means for selectively directing fluid to said motors for said ground engaging means to optionally dictate the nature of their movement on activation thereof, and means for selectively directing the flow of fluid to said vibrator motors and for selectively by-passing the flow in respect thereto, one of said means for directing fluid including speed selector control means, the said means for directing the flow of fluid to said vibrator motors including means selectively dividing the flow to such motors.
 23. A ground traversing machine, including a frame, a prime mover on said frame including means for supplying hydraulic fluid under pressure, at least one ground engaging roller drum in connection with said frame, a traverse circuit including means to direct hydraulic fluid furnished by said supply means to effect rotary drive of said drum, a vibrating circuit including other means to direct hydraulic fluid furnished by said supply means to effect vibration of said drum, a speed control valve in connection with said vibratory circuit adjustable to effect different modes of operating said machine in a first of which said drum is simultaneously driven and vibrated and in another of which said drum is rotatively driven at a speed higher than in the first said mode and is not vibrated, said valve having alternative positions of adjustment in one of which it permits flow through said vibratory circuit and in the other of which it denies flow through said vibratory circuit and diverts the hydraulic flow directed thereto to said traverse circuit, and another valve in connection with said vibratory circuit downstream of said speed control valve in reference to the direction of hydraulic flow settable to render said vibratory circuit alternatively effective and ineffective to vibrate said drum irrespective of the position of adjustment of said speed control valve.
 24. A ground traversing machine, including a frame having a prime mover thereon, at least one rotatable ground engaging means, means supporting said rotatable ground engaging means from said frame for relative vibratory and rotary motions, means powered from said prime mover to rotate said rotatable ground engaging means, other means powered from said prime mover to vibrate said rotatable ground engaging means, the said means powered from said prime mover cooperating to achieve traversal of the machine over ground surface with simultaneous drum vibration, speed control means selectively adjustable to divert the power supplied to vibrate said rotatable ground engaging means to achieve an augmented powering of the means to rotate said rotatable ground engaging means whereby the machine may selectively be conditioned for relatively rapid traversal without drum vibration, and other means settable to render said means to vibrate said rotatable ground engaging means alternatively effective and ineffective irrespective of the position of adjustment of said speed control means. 